When to use a confinement feedlot

maintenance feeding during a dry season when paddock feed is limited and erosion risk is high

deferred grazing during autumn in a normal year

finishing lambs.

Livestock should be removed from paddocks before groundcover drops to 50% or about 750kgDM/ha. These conditions greatly increase the risk of wind erosion. Confinement feeding is one option for managing those animals.

Indicators of a high risk are:

the peak pasture biomass in the previous spring – if it is a dry spring, significantly less biomass accumulates, and the limits for wind erosion are reached quicker than normal

the date of senescence/haying off – if it is an early finish, the critical limits for residual feed on offer (FOO) to prevent wind erosion will be reached earlier than normal

seasonal conditions through summer – summer rainfall and high temperatures increase the rate of breakdown of dry pasture.

Deferred grazing at the break of the season allows germinated plants to establish a root system and reach a leaf area that maximises pasture growth rate for the rest of the season. Grazing sooon after germination increases the risk of uprooting small seedlings. We recommend deferring grazing until there is at least 500 kilograms of dry matter per hectare (kg DM/ha) of feed on offer (FOO).

Advantages of confinement feeding

Confinement feeding:

minimises soil and nutrient loss from bare ground (prevents erosion)

preserves pasture density or allows pasture density to increase after the break

preserves pasture composition, preventing overgrazing of one plant species

prevents sheep 'chasing the green pick' and expending energy after the break

trees in the area can provide shade but have to be protected from grazing.

well-drained soils that are not too dusty when dry or muddy when wet

convenient to yards, silos and a water source.

close enough to base to allow regular checking of animals and minimise travel, but far enough to avoid the potential effects of dust and smell.

at low risk of nutrient run-off

at least 50 metres (m) from intermittently ﬂowing watercourses and 100m from permanent streams or rivers

away from dams so that run-off does not contaminate the dam

Mob size and confinement area

Mob size should be no more than 500 sheep, and farmer experience suggests mobs of 200 are better for young sheep. Allow 5 square metres (m2) per head: for a mob of 500 dry ewes, the conﬁnement system would need to be 2500m2 (for example, 50m x 50m or 25m x 100m).

Adjust the mob size to the class of sheep run in conﬁnement. Having more than one pen allows for sheep to be separated according to class or age and allows for pens to be spelled.

Feed troughs

Feed troughs are suited to maintenance feeding, where intake is restricted.

Feeding into troughs prevents feed wastage and reduces the risk of animal health problems (salmonellosis and coccidiosis). Troughs need not be pretty nor expensive - just functional. Troughs can be designed so that sheep have access to one side or both sides – it is important that the correct feed space is provided to reduce shy feeding.

For double-sided access to troughs, allow 15cm per lamb or 20cm per adult of trough length.

For single sided access to a trough, allow 30cm per lamb or 40cm per adult of trough length.

Raise troughs off the ground to reduce fouling. Lift the top edge up to 40–45cm for weaners and 50–55cm for adults. Adjust the height where a feed trailer has to straddle the trough

Self-feeders

Self-feeders can save labour in feedlots where the objective is to feed for production.

Self-feeders are more suited to ﬁnishing stock to a marketable weight – sheep can maximise feed intake.

Less trough space is required for self-feeders. Allow 4–5cm per lamb and 5–10cm per adult (use the upper end of this allowance for sheep with wool longer than 2cm). Sheep tend to arrange themselves better around circular self-feeders than rectangular self-feeders.

Lick-feeders

Lick-feeders can also be used in finishing systems but are more suited for providing supplementary rates of feed to stock for maintenance during drought or when pasture is limiting. They are also useful in stubbles. The ‘lick’ principle requires sheep to actively lick grain from restricted areas within a feed trough until ‘tongue-tired’.

Intake can be regulated to a few hundred grams of supplement daily, but intake rates can be variable. As with self-feeders, lick-feeders save on labour, wastage of feed, and reduce the proportion of shy feeders. There can be issues with blockages due to ‘fines’, and acidosis can still occur – lick-feeders are not a substitute for safe grain introduction.

Roughage

It is important to provide adequate roughage to confined-fed animals. In addition to a balanced ration, a minimum of 10–15% effective fibre needs to be supplied. Roughage:

surround large hay bales with weldmesh or panelling (such as portable sheep yards) – so that animals can still access the roughage source

use hayracks for large square bales

prevent sheep from climbing on top of hay bales or rolls – it is possible for bales to collapse and suffocate or crush sheep, especially lambs.

Water

A guaranteed supply of good quality water is essential in a conﬁnement feeding system. The amount of water consumed by sheep depends on the weather, type of feed, quality of water and their physiological stage (for example pregnant, lactating). Allow for 4–6 litres per sheep per day. Dams should be fenced out of the conﬁnement area and stock watered using troughs.

Troughs need to be cleaned regularly as contamination with faeces, dust and feed will reduce water intake.

Place water troughs at the opposite end to hay and feed sources to reduce fouling. A minimum trough length of 30cm plus 1.5cm per sheep (with one-sided trough access) is recommended for mobs of up to 500. For example, a trough length of 7.8m is the minimum requirement for a mob of 500 sheep. It is essential that pipe diameter and water pressure are adequate to ensure water can be supplied to troughs at all times.